// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE-BSD file. See the AUTHORS file for names of contributors.

#include "util/testutil.h"

#include "util/random.h"

namespace leveldb
{
namespace test
{

Slice RandomString(Random *rnd, int len, std::string *dst)
{
	dst->resize(len);
	for (int i = 0; i < len; i++) {
		(*dst)[i] = static_cast<char>(' ' + rnd->Uniform(95)); // ' ' .. '~'
	}
	return Slice(*dst);
}

std::string RandomKey(Random *rnd, int len)
{
	// Make sure to generate a wide variety of characters so we
	// test the boundary conditions for short-key optimizations.
	static const char kTestChars[] = {'\0', '\1', 'a', 'b', 'c', 'd', 'e', '\xfd', '\xfe', '\xff'};
	std::string result;
	for (int i = 0; i < len; i++) {
		result += kTestChars[rnd->Uniform(sizeof(kTestChars))];
	}
	return result;
}

Slice CompressibleString(Random *rnd, double compressed_fraction, size_t len, std::string *dst)
{
	int raw = static_cast<int>(len * compressed_fraction);
	if (raw < 1)
		raw = 1;
	std::string raw_data;
	RandomString(rnd, raw, &raw_data);

	// Duplicate the random data until we have filled "len" bytes
	dst->clear();
	while (dst->size() < len) {
		dst->append(raw_data);
	}
	dst->resize(len);
	return Slice(*dst);
}

} // namespace test
} // namespace leveldb
